P23E1EGR C Control Circuit/Open
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P23E1 covers the electrical drive of EGR valve C, a third exhaust gas recirculation actuator next to valves A and B. Which valve carries the letter C is up to the manufacturer; no carmaker documents P23E1 publicly. The code means the module has found the control circuit open or otherwise faulty. GM's 2018 diesel tables show how the A-side equivalent P0403 works: with the H-bridge driver off and the valve commanded away from closed, a load resistance above 200 kΩ in 96 of 120 samples sets the code as Type B, MIL after two trips. A similar check is plausible for valve C. CARB requires EGR components to be monitored for circuit faults. With this path disabled, NOx rises. Shorts are P23E3 and P23E4.
- What you may notice
- Warning lamp with otherwise normal driving
- Raised NOx at emissions testing
- Likely causes
- LikelyUnplugged or corroded connector at EGR valve C
- PossibleOpen motor winding or solenoid coil in valve C
- PossibleBroken drive wire between engine module and valve C
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €40 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.